Asthma, the leading chronic disorder in childhood, is the number one cause of pediatric emergency department (ED) visits in young children and is responsible for a substantial impact on healthcare costs.The ED is often the point of contact for low-income children and many families view the ED as their primary source of asthma care. Poor and minority children have the highest asthma morbidity, are the least likely to receive adequate preventive therapy or specialty care and more frequently exposed to environmental triggers than non-poor children. However, prior studies, including our pilot, indicate that childre with frequent asthma ED visits will attend a one-time ED-based follow-up clinic for an asthma check-up and education. The goal of this randomized controlled trial is to test the efficacy of a multifaceted, ED + primary care provider (PCP) and home-based intervention, Asthma Express (AEx), for children with > 2 asthma ED visits or 1 hospitalization/year that provides tailored guideline based asthma care. Allergy and cotinine biomarkers, collected during the ED visit, are used to target the home environmental control component of the intervention. The AEx intervention (n=132) will be compared to an attention control (CON) group (n=132) for the specific aims: (1) to reduce asthma morbidity (increase symptom free days and nights) and decrease ED visits and hospitalizations and increase asthma control and caregiver quality of life, (2) to improve the use of appropriate preventive anti-inflammatory medication based on child pharmacy refill records and (3) to compare the economic cost and effects of this intervention. Children aged 3-12 years with > 2 asthma ED visits or 1 hospitalization within the past 12 months and a current ED visit for asthma will be recruited from the Johns Hopkins Pediatric-ED and followed for 12 months. Symptom frequency, health care utilization, caregiver quality of life and cotinine measures will be collected at baseline, 6 and 12 months and pharmacy data collected at baseline and 12 months. Data analysis includes initial cross tabulations of health outcomes by group (AEx vs. CON) and multivariate generalized linear regression models to study the effects of the AEx treatment on mean symptom free days/nights, repeat ED visits, hospitalizations and caregiver quality of life scores and anti-inflammatory medication refills. Mean total costs of ED, PCP visits, hospital days and medication costs will be compared between groups (AEx and CON) for the economic analysis. The AEx model is designed to be accessible, guideline-based, easily replicated and incorporated into ED care. If successful, this study will fill critical gaps in the ED transition to preventive care asthma interventional research.